Double door construction and latch mechanism



Nov. 11, 1958 R. M. HADLEY 2,359,744

7 DOUBLE DOOR dous'raucnou AND LATCH MECHANISM Filed Feb. 18, 1955 2 Sheets-Sheet 1 Fit:

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R. M. HADLEY Nov. 11, 1958 DOUBLE DOOR CONSTRUCTION AND LATCH MECHANISM 2 Sheets-Sheet 2 Filed Feb. 18, 1955 United States Patent DOUBLE noon CONSTRUCTION AND LATCH MECHANISM Application February 18, 1955, Serial No. 489,039

6 Claims. (Cl. 126-197) This invention relates to a double door construction and a latch mechanism therefor and it is an object of this invention to provide improved apparatus of that character.

In various applications it is desirable to provide a double door for an opening in a cabinet. One such application is in the oven door of a stove. In the latter case it has been found difiicult to provide a satisfactory glass panel ina single door for an oven. Thishas resulted in the productionof some ovens with double doors, the outer door being solid and the inner door being provided with a glass panel to permit inspection of the interior of the oven Without permitting the .hot air to escape therefrom.

In accordance with one embodiment of the invention latch means are provided which permit the opening of both the inner and outer door in a single motion and alternatively permit opening of the outer door only, the I inner door remaining in closed position. In essence this .latchmechanism alternatively secures the inner door to of its being biased toward closed position.

Accordingly, it is another object :of the invention to provide an improved double door construction and ;latch mechanism therefor which permits alternativelatching of the inner door to thedoor frame and to the outer door.

It isano-ther objectof theinventionttoprovide an improved .double door construction and latch mechanism therefor which permits selective opening ofyboth doors or of just the outer door, the inner door gbeing secured in closed position when just the outer door is to be opened. I,

It is another object of the invention to provide an improved latch mechanism for application to a double doonsys'tem. I, a p

fit 'is another object of .t-hetinve ntion to provide improved apparatus having lthejcharacteristics described above While being simple,,1 :eliable, e fiicie nt and economical to-manufacture v d f This invention,- together with further objects and advantages thereof, will best be understood reference to thefollowing description taken in connection with' the accompanying drawings, and its scope will 'be pointed out in the appended claims.

In the drawings, in which like parts are designated by like reference numerals, v V

Figure 1 is across-sectional elevational view of one embodiment of theinvention,'both doo'rs being closed-and the latch mechanismbeing 'i'n 'its normal position.

Fig. 2 is a similar view showing both doors "opened. Fig. :3 is a viewsimilar to Figure l but showing the latch mechanism in its actuatedaposition. i

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Fig. 4 is a similar view showing only the outer door opened. I I

Fig. 5 is a plan view of a portion of the latch mechanism shown in Figure 1.

Fig. 6 is a front elevational view of that portion of the latch mechanism which is mounted on the door frame of Figs. 1-4.

Figure 7 is a perspective view of one element of the latch apparatus seen in Fig. 6.

As indicated above, one practical application of apparatus constructed in accordance with the present invention is to ovens where a solid outer door and a glass panelled inner door are frequently employed. It is to be understood, however, that the apparatus constructed in accordance with the present invention may be useful in numerous other applications where double doors are employed.

In the embodiment of the invention disclosed in the drawings, a cabinet, for example an oven 11, is provided with an outer door 12 and an inner door 13. The outer door is of a hollow double-walled metal construction While the inner door 13 comprises a single wall having .a glass panel 14 forming a part thereof. The purpose of the glass panel 14 is, of course, to permit inspection of the interior of the oven without permitting the escape of hot air therefrom. When the oven door is to be opened to provide access to the interior of the oven, it is desirable that both the inner and outer doors be opened as a unit. On the other hand, if the operator wishes to inspect the interior of the oven, it is desirable that only the outer door he opened and that the inner door be maintained securely and tightly shut. It is the purpose of the latch mechanism, shown in the drawings, to acthe outer door 12, a suitable pad 18 being securedat o the arm 17 as by the set screw 19. The pad 18 provides a convenient and comfortabl'esurface for contact by ,the operators fingers or thumb.

The latch bolt 15 also includes a downwardly extendi'n'g arm 20 which engages a coil spring 21, the latter being in compression between the arm 20 and the inner wall of the outer door 12. It will be seen .thatthe spring 20 biases the latch bolt 15 in a clockwise direction, as viewed in Figs. 14. d g I Finally, the latch bolt 15 includes an inwardly extendinghook 22, this hook extending through an opening 12' in the inner wall of the outer door and throughan opening 13 in the inner door. d V

Mounted on the oven 11 is a latch mechanism 23. This mechanism includes a sliding latch bolt 24. As may be seen best in Fig. 6, the sliding latch bolt 24 has an opening 25 therein for receiving the hook 22 of the pivotal latch bolt 15. The sliding latch bolt 24 also has three slots 26, through which pass rivetsor screws 27. The fasteners 27 are-headed, as seen in Figs. l-4 whereby they hold the sliding latch bolt '24 securely, but-loosely, to the oven. The slots 26 permit vertical sliding movement of the latch bolt, and a spring 28, best seen in Fig. 7, is arranged between the sliding latch bolt 24 and the oven, whereby the sliding latch bolt is frict'ionally maintained in either of its two operating positions.

It will be noted in Figs. 14 that the inner door--13 is bent near the upper edge thereof and that the opening 13 therein extends into the short horizontal portion of the inner door produced by this'bend. The sliding latch bolt 24 is arranged to slide upwardlythr'ough the opening 13 and engage the fixed keeper element whichiszthe uppermostportion of theinner door 13, as is readily seen i in Figs. 3 and 4. When the sliding latch bolt 24 is in this position, the inner door 13 is held shut. When the sliding latch bolt 24 is moved to its lower position, as seen .in Figs. 1 and 2, it no longer engages the inner door 13,

whereby the latter is free to swing open.

When the hook 22 of the pivotal latch bolt 15 extends through the opening 13 in the inner door 13 and the pivotal latch bolt is released so that thespring 21 may force the latch bolt in a clockwise direction, the hook 22 is in position to engage the inner door 13, all as i readily .seen in Figs. 1 and 2.

When the hook 22 extendsthrough the opening 13 in the inner door and is allowed to pivot in a clockwise direction, it also actuates the sliding latch bolt 24. In Fig. 3 it will be seen that the lowermost portion of the hook 22 is arranged immediately above and is adapted to abut the lower central portion of sliding latch bolt 24. Accordingly, when the handle 18 of the pivotal latch bolt 15 is released, the spring 21 not only pivots the latch bolt 15 in a clockwise direction to a position to engage the inner door, but also moves the slidable latch bolt downwardly to the position illustrated in Fig. l in which'it is disengaged from the inner door.

Furthermore, when the pivotal latch bolt 15 is manually moved in a counter-clockwise direction, from the position of Fig. l to the position of Fig. 3, disconnecting the outer door from'the inner door, the upper edge of the hook 22 engages the upper central portion of the sliding latch bolt 24 and raises it, to secure the inner door to the oven. 1

Preferably the outer door 12 is biased by sprnigs or by counterweights toward its closed position, as is conventional in oven doors. The inner door 13 requires no biasing since it is always secured to either the outer door 12 or the oven 11.

The operation of the above-described modification of the invention may best be described starting with the position illustrated in Fig. 1. In this position the sliding latch bolt 24 is in its lower position in which it is disengaged from the inner door 13. The hook 22 extends through the opening 13 and is in its lower position in which it is engaged with the inner door. If the outer door is now opened, the inner door will be pulled along with the outer door, as illustrated in Fig. 2. Access is thereby provided to the interior of the oven. .When the doors are again closed, the hook 22 moves through the ,opening25 in the sliding latch bolt 24 without operavsliding latch bolt 24 upwardly so that it passes through the opening 13 and engages the. upper extremity of the inner-door 13, all as previously described and as shown in Fig. 3. Now when the outer door 12 is opened, the hook 22 passes freely past the inner door 13, and the inner door is maintained securely in closed position by the sliding latch bolt 24.

During the time that the outed door is open, the op erator; will logically release the handle 18, whereby the spring 21 returns the pivotal latch bolt 15 to its normal position as illustrated in Fig. 4. After inspection of the interior of the oven through the glass panel 14 in the inner door 13, the outer door may be returned manually or by means of a spring 12" to its closed position without 'manual operation of the pivotal latch bolt 15.

In this operation the lower sloping surface of the hook 22 rides upwardly over the edge of the inner door which defines the lower end of the slot 13, thereby forcing the pivotal latch bolt 15 to pivot in a counterclockwise direction against the action of the spring 21. When the lip of the hook 22 passes beyond the inner door 13, the spring 21 moves the pivotal latch bolt in a clockwise direction, returning it to its normal position. At the same time the hook 22 engages the edge of the sliding latch bolt 24 which defines the lower end of the slot 25 and forces the sliding latch bolt downwardly from the position of Figs. 3 and 4 to the position of Fig. 1. It should be noted that the spring 21 is preferably of suflicient strength to move the pivotal latch bolt in a clockwise direction and to move the sliding latch bolt in a downward- 1y direction against the frictional effect of the spring 28.-

Preferably a conventional, fixed oven door handle (not shown in the drawings) is provided on the outer surface of the outer door. This handle is preferably placed at the same level or slightly below the handle or pad 18. With the fixed oven door handle and the movable handle 18 so arranged, the operator can perform any desired operation of the oven doors with one hand. For example, the operator can grasp the fixed handle with his fingers, and if he wishes to depress the handle 18 this can be done with the thumb of the same hand.

In the particular embodiment of the invention illustrated in the drawings and described above, movable latch elements are provided on the outed door and on the oven proper. Since the function of the over-all latch mechanism, and the essence of the present invention, is a double door arrangement and a cooperating latch mechanism which alternatively secures the inner door to either the outer door or the oven, it will readily be apparent that a single movable latch element might be mounted on the inner door and arranged to engage fixed or movable latch elements on the oven and on the outer door alternatively. While such an arrangement is practicable and falls within the scope of the invention, it is not the preferred arrangement, and hence it not described in detail herein.

As previously indicated, the present invention appears to have particular applicability to ovens, since in this application there is an established need of a double-door construction. However, it is tobe understood that the invention is in no sense limited to application to ovens, as there are many other applications in which the use of a double-door arrangement might be desired.

While particular embodiments of the invention have been shown, it will be understood, of course, that the invention is not limited thereto since many modifications may be made, and it is, therefore, contemplated to cover by the appended claims any such modifications as fall within the true spirit and scope of the invention.

It will be apparent that the invention may be varied in its physical embodiments without departing from the spirit of the invention.

' I claim:

1. In a double door construction for a cabinet comprising an inner door and an outer door, both for closing an opening in said cabinet, said doors being hinged to said cabinet adjacent the lower side of said opening and said outer door being biased toward closed position,

an improved latch means .for releasably connecting said inner door alternatively to said outer door and to said cabinet, said latch means comprising an element pivotally mounted on said outer door, a fixed keeper element on said inner door, and an element slidably mounted on said cabinet, said pivotable element and said slidable element each being movable between a latching and a released position with respect to said keeper element, said 2. In a double door construction for a cabinet comprising an inner door and an outer door, both for closing an opening in said cabinet, said doors being hinged to said cabinet adjacent the lower side of said opening and said outer door being biased toward closed position, an improved latch means for releasably connecting said inner door alternatively to said outer door and to said cabinet, said latch means comprising an element pivotally mounted on said outer door, a fixed keeper element on said inner door, and an element slidably mounted on said cabinet, said pivotable element and said slidable element each being movable between a latching and a released position with respect to said keeper element, said pivotable element being engageable with said slidable element when said doors are closed and being arranged to move said slidable element into said released position when said pivotable element moves into said latching position and to move said slidable element into said latching position when said pivotable element moves into said released position, said pivotable element being biased toward said latching position.

3. In a double door construction for a cabinet comprising an inner door and an outer door both for closing and opening in said cabinet, said doors being hinged to said cabinet adjacent the lower side of said opening and said outer door being biased toward closed position, an improved latch means for connecting said inner door alternatively to said outer door and to said cabinet; said latch means comprising a fixed keeper mounted on said inner door, a first element mounted on the outer door and movable into and out of engagement with the keeper, 2. second element mounted on said cabinet and movable into and out of engagement with said keeper, said first element being engageable with said second element to effect movement thereof to the keeper engaging position, when said first element is moved to its keeper releasing position.

4. In a double door construction for a cabinet comprising an inner door and an outer door both for closing and opening in said cabinet, said doors being hinged to said cabinet adjacent the lower side of said opening and said outer door being biased toward closed position, an improved latch means for connecting said inner door alternatively to said outer door and to said cabinet; a keeper mounted on the inner door, a first element mounted on the outer door and movable into and out of engagement with said keeper, a second element mounted on said cabinet and movable into and out of engagement with said keeper, said first element being movable toward the keeper releasing position and being simultaneously engageable with said second element to effect movement thereof toward the keeper engaging position, spring means urging said first element toward its keeper engaging position.

5. In a double door construction for a cabinet comprising an inner door and an outer door both for closing and opening in said cabinet, said doors being hinged to said cabinet adjacent the lower side of said opening and said outer door being biased toward closed position, an improved latch means for connecting said inner door alternatively to said outer door and to said cabinet; a keeper mounted on the inner door, a first element mounted on the outer door and movable into and out of engagement with said keeper, a second element mounted on said cabinet and movable into and out of engagement with said keeper, said first element being engageable with said second element to eliect movement of said second element into its keeper releasing position when said first element is moved to its keeper engaging position and to effect movement of said second element toward its keeper engaging position as said first element is moved toward its keeper releasing position and spring means urging said first element toward its keeper engaging position and thereby adapted to urge said second element toward its keeper releasing position.

6. In a double door construction for a cabinet comprising an inner door and an outer door both for cl0sing and opening in said cabinet, said doors being hinged to said cabinet adjacent the lower side of said opening and said outer door being biased toward closed position, an improved latch means for connecting said inner door alternatively to said outer door and to said cabinet; a keeper mounted on said inner door, an element mounted on said outer door and pivotally movable between a keeper engaging and a keeper releasing position, said element having an inwardly extending hook-like arm for engaging said keeper and a lever-like handle for permitting manual movement of said bolt to its keeperreleasing position, spring means urging said element toward its keeper engaging position, a slidable element mounted on said cabinet and movable between a keeper engaging and a keeper releasing position, said pivotally movable element during movement to its keeper releasing position being adapted to engage said slidable element to effect movement thereof toward its keeper engaging position.

References Cited in the file of this patent UNITED STATES PATENTS 40,465 Flansburgh Nov. 3, 1863 192,521 Martin June 26, 1877 237,827 Day et al. Feb. 15, 1881 434,893 Scott Aug. 19, 1890 543,454 Sievers July 23, 1895 2,122,680 Dart July 5, 1938 2,243,772 Peltier May 27, 1941 2,309,049 Curtiss Jan. 19, 1943 

